The only way to get rid of hordes would be to remove missions (Since that's where most come from).
Removing missions would be removing a lot of organization.
Removing organization would remove teamwork.
I hate to say it guys... But hordes are a form teamwork, no matter how you cut it. It just sucks when one team can get that many people together when the other cannot. But like many have said, it's not impossible to defend or at least slow down.
One thing that I'm fairly confused by is the people who are worried about the hordes are the ones who say that base-taking doesn't matter, and that fighting is the point of the game. So, why are they worried about the other team taking their bases because those other people like doing so? I don't understand why people who don't care don't completely ignore the hordes and keep on fighting elsewhere.
The people who should be worried about hordes are the ones who want to win the war, however most of those people do something to counter the mass attacks, and they seem to have fun. There is no reason to throw yourself into a horde if you are just going to come on the forum and complain about it (not to say that the OP is complaining, just a generality).
Those people are clearly having fun, and letting them ruin your fun is fruitless, and quite frankly a waste of your time. This is a Massively Multiplayer Online game. Things are massive with multiple people online doing the same thing. Definition of a horde. MMO is code for horde, and it happens in every single MMO. The only difference: in other MMO's, people understand that it's how human nature works, and use tactics to counter it.
I'll take EVE Online as an example. I've spent some time in this game, but recently stopped playing just because I simply got bored. It became a bit of a grind and the same thing day in and day out, not worth my time. Anyway, combat in that game is a similar concept as this one. Sometimes you find 1v1's, sometimes you start a 1v1 and friends show up and "pick" you. Sometimes you just happen to be a victim of a roaming "horde" of people patrolling low and null-sec. At least in this game, you don't have to buy a new plane. But I'll tell you what, if you are informed of a horde in a certain system, you sure as hell don't go headlong into it by yourself. You go around, and if you have a big enough group, you form an attack from the rear. Funny thing is, when you go on the EVE Online forums, if someone were to whine about a roaming horde, they would get laughed right out. People know the risks of going certain places, hell we even have more warning systems to tell us about a horde coming than real life pilots did.
Basically what I am saying is, I don't think hordes are a sign of weakness, I think they are a show of human nature. To change hording in game, you'd have to change people outside of it (and I think we've had a few years of evolution that's made us this way).